Constructing InP/ZnSe Quantum Dots with Shell Gradient In3+ Doping for Photoelectrochemical Cells

• Environmentally friendly InP/ZnSe core/shell quantum dots (QDs) with high absorption coefficients and tunable band gaps have demonstrated great potential for photoelectrochemical (PEC) water splitting. However, the tightly bound excitonic feature by inherent type I band alignment tends to reduce the charge separation efficiency, limiting their PEC performance. Herein, we devised heterovalent In3+ gradient doping in the ZnSe shell of InP QD to construct core/shell structural InP/ZnSe-G-In QDs. The In3+ dopant increased the Fermi level of the ZnSe shell; thus continuous semiconductor homojunction and band bending were formed by gradient composition doping, which accelerates the exciton separation through the built-in electric field. As a result, the PEC cells based on such QDs exhibited high photocurrent density of 8.7 mA/cm2, demonstrating one of the highest values for the InP-based QDs PEC cells. This work provides an effective strategy for the application of type I band structure QDs in solar energy conversion.

Subject headings

NATURVETENSKAP  -- Kemi -- Materialkemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Materials Chemistry (hsv//eng)

NATURVETENSKAP  -- Kemi -- Fysikalisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Physical Chemistry (hsv//eng)

Publication and Content Type

art (subject category)

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